package com.xuecheng.framework.exception;

/**
 * @Author: huaiyu.gao -_- -_-
 * @Date: 2021/11/8 16:00
 */

import com.google.common.collect.ImmutableMap;
import com.xuecheng.framework.model.response.CommonCode;
import com.xuecheng.framework.model.response.ResponseResult;
import com.xuecheng.framework.model.response.ResultCode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
//使用SpringMvc的ExceptionHandler 捕获异常
@ControllerAdvice
public class ExceptionCatch {

    private static final Logger LOGGER = LoggerFactory.getLogger(ExceptionCatch.class);
    //使用EXPTIONS存放异常类型和错误代码的映射，ImmutableMap的特点是一旦创建不可改变，并且现场安全
    private static ImmutableMap<Class<? extends Throwable>,ResultCode> EXCEPTIONS;
    //使用builder来构建一个异常类型和错误代码的异常
    protected  static ImmutableMap.Builder<Class<? extends Throwable>,ResultCode> builder = ImmutableMap.builder();

    //捕获CustomException异常
    @ExceptionHandler(CustomException.class)
    @ResponseBody
    public ResponseResult customException(CustomException e){
        LOGGER.error("catch exception: {}\r\nexception:",e.getMessage(),e);
        ResultCode resultCode = e.getResultCode();
        ResponseResult responseResult = new ResponseResult(resultCode);
        return responseResult;
    }

    //捕获未知异常
    @ExceptionHandler(Exception.class)
    @ResponseBody
    public ResponseResult exception(Exception e){
        //记录日志
        LOGGER.error("catch exception:{}",e.getMessage());
        if (EXCEPTIONS == null) {
            EXCEPTIONS = builder.build();
        }
        final ResultCode resultCode = EXCEPTIONS.get(e.getClass());
        final ResponseResult responseResult;
        if (resultCode!=null) {
             responseResult = new ResponseResult();
        }else {
            responseResult = new ResponseResult(CommonCode.SERVER_ERROR);
        }
        return responseResult;
    }

    static {
        //在这里加入一些基础的异常类判断
        builder.put(HttpMessageNotReadableException.class,CommonCode.INVALID_PARAM);
    }
}
